In the Attach to Process dialog box, select the MATLAB process
and click Attach.

Visual Studio loads data then displays an empty code pane.

Open the source file yprime.c by
selecting File > Open > File. Locate yprime.c in
the folder, c:\work.

Set a breakpoint by right-clicking the desired line
of code and following Breakpoint > Insert Breakpoint on the context
menu. It is often convenient to set a breakpoint at mexFunction to
stop at the beginning of the gateway routine.

If you have not yet run the executable file, ignore any "!"
icon that appears with the breakpoint next to the line of code.

Once you hit one of your breakpoints, you can make full use
of any commands the debugger provides to examine variables, display
memory, or inspect registers.

Open MATLAB and type:

yprime(1,1:4)

yprime.c is opened in the Visual Studio debugger
at the first breakpoint.

If you select Debug > Continue, MATLAB displays:

ans =
2.0000 8.9685 4.0000 -1.0947

For more information on how to debug in the Visual Studio environment,
see your Microsoft documentation.

Notes on Debugging

Binary MEX-files built with the -g option
do not execute on other computers because they rely on files that
are not distributed with MATLAB. For more information on isolating
problems with MEX-files, see Troubleshoot MEX-Files.